1. Field of the Invention
This invention relates to the novel preparation of 2-(2-bromo-2-nitroethenyl)-furan (BNEF) and to its uses as a broad spectrum antimicrobial agent.
2. Description of the Art
A number of industrial organo-bromine nonoxidizing antimicrobials, including .beta.-bromo-.beta.-nitrostryene, are known. Nonoxidizing antimicrobials are used in many industrial systems in which strong oxidizing antimicrobials such as chlorine or bromine cannot be used. Industrial systems generally requiring nonoxidizing antimicrobials include water systems, pulp and paper manufacturing, metal working fluid preservation, latex paint preservation, wood preservation, cosmetics preservation, oil field and institutional hard-surface disinfection. However, despite the many commercially available nonoxidizing antimicrobials, none are entirely suitable for every application due to efficacy, safety, environmental acceptability and cost.
The antimicrobial activity of various 2-furylethylenes, such as 2-(2-nitroethenyl)-furan is also well known. The literature suggests that the microbiocidal activity of the nitroethenylfurans is not sufficient for industrial antimicrobial application unless the furan ring has a 5-nitro substitution. Unfortunately, 5-nitro substituted furan antimicrobials are mutagenic and, in some cases, even carcinogenic in rodents; therefore, 5-nitrofuran derivatives are unsuitable for industrial applications. However, the prior art has failed to recognize the effective antimicrobial activity of 2-(2-bromo-2-nitroethenyl)-furan (BNEF) as an nonoxidizing antimicrobial.
Russian Patent 1,027,663, issued Jan. 1, 1967, discloses the usage of furylnitroalkylenes as antimicrobials. The furylnitroalkyenes are applied to the root zone of a plant or to the soil to control nematodes.
Nazarova and Potemkin in an article entitled "Synthesis of Some Furylnitroolefins with Potential Biological Activity" describe the laboratory preparation of selected furylnitroolefins including BNEF. The process used to prepare BNEF utilizes an 100 percent stoichiometric excess of aqueous potassium hydroxide as a catalytic agent. However, it has been found that the BNEF formed by the described process is undesirably contaminated with nonbrominated nitroethenylfuran, a compound with lower antimicrobial activity.
The Russian article "Physiochemical Properties and Reactivities of Furylnitroolefins" by Gruntfest, et al., discloses the physiochemical properties, structures and reactivities of a series of furylnitroolefins. The article fails to disclose the antimicrobial activities of any of the studied furylnitroolefins.
Japanese Patent 59/184463 discloses a antimicrobial use of nitroethenylfuran used as a component of an antifouling coating for ship bottoms.
Accordingly, a primary object of the present invention is the development of a new broad spectrum industrial antimicrobial agent incorporating 2-(2-bromo-2-nitroethenyl)-furan.
Another object is to obtain a new broad spectrum antimicrobial agent of the character described that is nonoxidizing.
A still further object is to provide an improved process for producing 2-(2-bromo-2-nitroethenyl)-furan which eliminates formation of nonbrominated nitroethenylfuran.